Three out of five older people given a dietary supplement have reported feeling fitter to US researchers.

An amino acid essential in developing muscles during exercise, Beta-alanine, is often found in body building powders and drinks.

It helps muscles work by stopping them getting too tired and results in the body gaining more muscle.

The amino acid is thought to possibly help prevent older people suffering falls by making their muscles stronger.

Scientists from the University of Oklahoma asked a study group of 26 older people to try the athletes’ supplement, giving half a placebo.

Of the group, 67 per cent of those people taking beta-alanine reported feeling fitter, while only 21.5 per cent of those given placebos reported an improvement in fitness.

Study leader Jeffrey Stout said: "This could have importance in the prevention of falls and the maintenance of health and independent living in elderly men and women."

Beta-alanine is found via dipeptides found in protein-rich food like chicken, pork, beef and fish.